A nutrient medium that has all of its chemical components identified and their precise concentrations known and reproducible would be termed
synthetic
Pasteur used swan-neck flasks in his experiments to prove that
dust in air was a source of living microorganisms.
Select the correct descending taxonomic hierarchy (left to right):
family, genus, species
A common medium used for growing fastidious bacteria is
blood agar
The three physical forms of laboratory media are: solid, semisolid, and _____.
liquid
TRUE or FALSE: A selective medium contains one or more substances that inhibit growth of certain microbes in order to facilitate the growth of other microbes.
TRUE
A microbiologist inoculates Staphylococcus aureus into a culture medium. Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis are determined to be growing in this culture. What is the most likely explanation?
The culture is contaminated.
TRUE or FALSE: Identification relies entirely on biochemical test results.
False
Disease-causing microorganisms are called
pathogens.
The primary purpose of staining cells on a microscope slide is to
add contrast in order to see them better.
If a microbiologist is studying a specimen at a total magnification of 950X, what is the magnifying power of the objective lens if the ocular lens is 10X?
95X
Which of the following is the correct way to type the scientific name of this bacterium?
Staphylococcus aureus
Where are you most likely to find bacteria belonging to the domain Archaea?
in a hot spring
Taxonomy does not involve
Koch's postulates.
TRUE or FALSE: Mixed cultures are also referred to as contaminated cultures.
False
A media is designed that allows only staphylococci to grow. In addition, Staphylococcus aureus colonies have a yellow halo around them and other staphylococci appear white. This type of media is
both selective and differential.
TRUE or FALSE: At the end of the Gram stain, gram-positive bacteria will be seen as purple cells.
True
Bacteria that require special growth factors and complex organic substances are called
fastidious.
The term that refers to the purposeful addition of microorganisms into a laboratory nutrient medium is
inoculation.
The scientific field called_____ is involved in the identification, classification, and naming of organisms.
taxonomy
Which of the following is not considered a microorganism?
mosquito
Newly inoculated cultures must be _____ at a specific temperature and time to encourage growth.
incubated
This microscope achieves the greatest resolution and highest magnification:
electron
TRUE or FALSE: A medium that is gel-like has less agar in it compared to a solid medium.
TRUE
The Six I's of studying microorganisms include all of the following except
infection.
Which of the following is a taxon that contains all the other taxa listed?
kingdom
TRUE or FALSE: One distinguishing characteristic of the archaebacteria is that they live in extreme environments.
True
All of the following are examples of different types of microbiological media except
petri dish.
All of the following are correct about agar except
it is a source of nutrition for bacteria.
Which of the following is a unique characteristic of viruses that distinguishes them from the other major groups of microorganisms?
lack cell structure
Magnification is achieved in a compound microscope through the initial magnification of the specimen by the _______ lens. This image is then projected to the _______ lens that will further magnify the specimen to form a virtual image received by the eye.
objective, ocular
TRUE or FALSE: The names of the three proposed Domains are: Bacteria, Protista, Eukarya.
False
When assigning a scientific name to an organism,
both genus and species names are italicized or underlined.
Which of the following will result when 1% to 5% agar is added to nutrient broth, boiled and cooled?
a solid medium
TRUE or FALSE: All microorganisms are parasites.
False
The type of microscope in which you would see brightly illuminated specimens against a black background is
dark-field.
Koch's postulates are criteria used to establish that
a specific microbe is the cause of a specific disease.
Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium?
differential
A pure culture contains only
one species of microorganism.
one species of microorganism.
Subculture
Bacteria that require special growth factors and complex nutrients are termed _____.
fastidious
Define Microbe:
organism that is invisible to the naked eye seen only under magnification or with a microscope
What is the largest bacteria?
Thiomargarita magnifica
How does Dr. Bali B define microbiology?
the study of cellular and acellular organisms, most of which are usually too small to be seen without the aid of a microscope
Biotechnology is
the exploitation of biological processes to make industrial products, foods, or drugs
Genetic Engineering is
manipulation of the genes of microbes, plants, and animals
Bioremediation is:
the introduction of microbes into the environment to restore stability or clean up pollutants
Define Infectious diseases
caused by pathogens and can be spread
Define Noninfectious diseases
not caused by pathogens and cannot be spread example would be diabetes
Define emerging diseases
new diseases, not previously seen in a population
Define re-emerging diseases
"old" diseases previously seen in a population but are increasingly being seen in the population
What are the 3 classifications of organisms that cause disease
Obligate, Accidental, or Opportunistic
Describe Obligate pathogens
must have a host to stay alive, ALL viruses are an example
Describe Opportunistic pathogens
Only cause disease under unusual circumstances most time when people are immunocompromised. Example is Pseudomonas aeruginosa
Describe Accidental pathogens
thrive in the environment and can only infect under unusual circumstances. Example is Clostridium tetani
Who invented cell theory
Robert Hooke
Who was the first to observe unicellular organisms
Anton van Leeuwenhoek
Compound microscopes have ____ lens to produce a _______ image and enable ______________ an object
2 or more lens, to produce a 2D image, to look through an object
What is germ theory of disease and who came up with it
That disease is caused by tiny, invisible, organisms, Joseph Lister
WHAT ARE KOCH'S POSTULATES!?!?
1. The organism must be present in all cases of the disease
2. The organism must be isolatable from the infected host and grown in a pure culture
3. Pure culture of the organism must cause the same disease in a new host
4. The organism must be reisolated from the new host and identified as identical to the original causative agent of the disease
What is a vaccine and what does it do?
stimulate production of antibodies and provide immunity against disease prepared from agent of disease
what does ELISA stand for
Enzyme-Linked Immunosorbent Assay
What is Selective Media
It contains 1 or more agents that inhibit growth of some microbes and encourage growth of the desired microbes
Who developed the 5 kingdom system for classifying living things
Robert H. Whittaker
What is a strain
is a population of organisms that have some slight differences between themselves and other member of the species
for eukaryotes "species" refers to what?
organisms that can interbreed
for prokaryotes "species" refers to what?
organisms that are similar
Describe a dichotomous key
tools for identification and pays no attention to how related organisms are
describe a cladogram
used in classification and are used to describe how closely related organisms are
WHAT ARE THE 6 I's IN ORDER!!!
Inoculation
Incubation
Isolation
Inspection
Information gathering
Identification
Complex or nonsynthetic media
contains at least one ingredient that is not chemically definable
General purpose media
grows a broad range of microbes, usually nonsynthetic
Enriched media
contains complex organic substances such as blood, serum, hemoglobin, or special growth factors required by fastidious microbes
Synthetic media
contains pure organic and inorganic compounds in an exact chemical formula
Selective media
contains one or more agents that inhibit growth of some microbes and encourage growth of the desired microbes
Differential media
allows growth of several types of microbes and displays visible difference among those microbes
Give an example of microbes that need live media
All viruses, some bacteria, and certain protozoa
What is Serology
the study of serum and immune responses
What is a genophore?
prokaryotic genetic material/nucleic acid/chromosome material
What is the glycocalyx
surface coating allowing cells to attach to each other can form biofilms
Monotrichous flagella
just 1 flagella
Lophotrichous flagella
flagella bunched together
Amphitrichous flagella
flagella on both sides
Peritrichous flagella
flagella all over
Chemotaxis respond to _______ stimuli and phototaxis respond to ________ stimuli
Chemical, Light
Fimbriae
fine hairlike bristles, that function in adhesion to other bacterial/prokaryotic cells and surfaces
Pili
rigid tubular structure made of pilin protein, found only in gram-negative bacteria, function to join bacterial cells for partial DNA transfer called conjugation
What are the two types of glycocalyx
Slime layer - mucoid, loosely organized and attached, prevents drying out and nutrients
Capsule - highly organized, tightly attached, contribute to pathogenicity causes the immune system confusion
Gram-positive bacteria
thick cell wall composed primarily of peptidoglycan and cell membranes
Gram-negative bacteria
outer cell membrane, thin peptidoglycan layer, and cell membrane
All bacterial cells have
a chromosome.
Which of the following are present in viruses?
none of the above
Fungi that grow as yeast at one temperature but will grow as mold at another temperature are called
dimorphic.
What is the correct sequence for a Gram stain?
Crystal Violet, Gram's iodine, Alcohol, Safranin
TRUE or FALSE The term diplococci refers to an irregular cluster of spherical bacterial cells.
False
If bacteria living in salty seawater were displaced to a freshwater environment, the cell structure that would prevent the cells from rupturing is
cell wall
The cytoskeleton
All of the choices are correct.
The difference in cell wall structure of Mycobacterium and
Nocardia
compared to the typical
gram-positive bacterial cell wall structure is
predominance of unique, waxy lipids.
Which term is not used to describe bacterial cell shapes?
tetrad
A prokaryotic cell wall that has primarily peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is
gram-positive.
TRUE or FALSE If during the Gram stain procedure, the bacterial cells were viewed immediately after crystal violet was applied, gram-positive cells would be purple but gram-negative cells would be colorless.
False
All of the following are found in some or all protozoa except
cell wall.
When a eukaryotic cell is not
undergoing
mitosis, the DNA and its associated proteins appear as a visible
thread-like mass called the
chromatin.
TRUE or FALSE Infections caused by fungi are called mycoses.
True
The transfer of genes during bacterial conjugation involves rigid, tubular appendages called
sex pili.
TRUE or FALSE Archaea do not have the typical peptidoglycan structure found in bacterial cell walls.
True
All of the following structures contribute to the ability of pathogenic bacteria to cause disease, except
inclusions.
All of the following pertain to endotoxins, except they
are found in acid fast bacterial cell walls.
The smooth endoplasmic reticulum functions in synthesis of ___________.
lipids
Magnetosomes are
composed of magnetic iron oxide particles.
Which of the following is the cause of malaria?
Plasmodium
The size of a eukaryotic cell ribosome is
80S
Lysozyme, an enzyme found in tears, provides a natural defense against bacteria by
hydrolyzing peptidoglycan in cell walls.
The short, numerous appendages used by some bacterial cells for adhering to surfaces are called
fimbriae.
TRUE or FALSE Endospores of certain bacterial species can enter tissues in the human body, germinate, and cause an infectious disease.
True
Blooms of certain dinoflagellates are associated with all of the following except
euglenids.
In order to reproduce sexually, diploid cells must produce _________ gametes through ________.
haploid, meiosis
TRUE or FASLE Gram-negative bacteria do not have peptidoglycan in their cell walls.
False
Which is mismatched?
Plasmodium - causes Chagas disease
The organelle involved in intracellular digestion of food particles is the
lysosomes.
Protists include
algae and protozoa.
Which is not a characteristic of fungi?
photosynthetic
In the Gram stain, the mordant is
Iodine.
The motile, feeding stage of protozoa is called the
trophozoite.
Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?
mitochondria
A microoganism has been described to you as living in hot acidic habitats in the waste piles of coal mines that regularly sustain a pH of 1 and a temperature of nearly 60°C. Which type of organism do you immediately assume it is?
Archaea
TRUE or FALSE If you observe rod shaped, pink cells on a slide that had just been gram stained, you can assume that their cell walls contain endotoxin.
True
Sarcinae refers to
a cuboidal packet of cells.
Chitin is a chemical component of the cell walls of
fungi.
TRUE or FALSE All algae have chloroplasts.
True
Lipopolysaccharide is an important cell wall component of
gram-negative bacteria.
The bacterial chromosome
is part of the nucleoid.
An organelle that is a stack of flattened, membranous sacs and functions to receive, modify, and package proteins for cell secretion is the
Golgi apparatus.
The outcome of the Gram stain is based on differences in the cell's
cell wall.
Endospores are
All of the choices are correct.
The periplasmic space is
an important reaction site for substances entering and leaving the cell.
All of the following are correct about helminthes except
they generally make only a few eggs per day
The term that refers to the presence of flagella all over the cell surface is
peritrichous.
The eukaryotic cell's glycocalyx is
mostly polysaccharide.
Which of the following is found in eukaryotic cells but not in prokaryotic cells?
All of the choices are correct.
Bacteria with small bunches of flagella emerging from the same site are said to be
lophotrichous
Both fish and humans develop neurological symptoms and bloody skin lesions due to a sudden "bloom" of this algae.
Pfiesteria piscida
A bacterial genus that has waxy mycolic acid in the cell walls is
Mycobacterium.
Which is mismatched?
plasmids - genes essential for growth and metabolism
All of the following are correct about a slime layer, except
it plays a role in cell motility.
TRUE or FALSE Bacteria in the genus Mycoplasma and bacteria called L-forms lack cell walls.
True
Which of the following, pertaining to prokaryotic cell membranes, is mismatched?
unique hydrocarbon present - cyanobacteria
The cell's series of tunnel-like membranes functioning in transport and storage are the
endoplasmic reticulum
Cilia are found in certain
protozoa.
TRUE or FALSE Iodine is the decolorizer in the Gram stain.
False
Larvae and eggs are developmental forms of
helminths.
Which statement is not a characteristic of biofilms?
They involve bacteria only.
Bacterial endospores are not produced by
Staphylococcus.
Chemical analysis of a bacterial cell structure detects calcium dipicolinic acid. What is the identity of this structure?
endospore
A bacterial cell exhibiting chemotaxis probably has
flagella.
Fungal spores
are used to identify fungi.
TRUE or FALSE Algae are classified into Divisions based principally on their type of motility.
False
When you use alcohol as the decolorizer what are you doing to the cell?
washing away the outer layer in Gram negative bacteria that contains lipopolysaccharides
What is the correct procedure to Gram stain?
1. Crystal violet - primary
2. Iodine - mordant
3. Alcohol - decolorizer
4. Safranin - counterstain to make Gram - appear pink
Give examples why pure cultures may show both Gram + and Gram - results
old, over decolorized, indeterminate, uneven decolorization, too thick of a smear of cells
What does pleomorphic mean?
size and shape differences in a single species
What are the two forms of plasmids?
Relaxed - free in cytoplasm, replicate independently
Stringent - integrated in chromosome, replicates when genome replicates "episome"
what does mean polyhydroxybutyrate mean
source of nutrients, not soluble
What are endospores?
inert, resting, cell produced by some G + genera, example Bacillus, Clostridium, and Sporosarcina
What does the vegetative state of endospore mean
they are metabolically active and growing
What does the sporulation state of an endospore mean
formation of endospores, can withstand extreme conditions, not a means of reproduction
What is the germination state of an endospore mean
return to vegetative growth
Ferdinand Julius Cohn did what?
Classified bacteria into four groups based on shape (spherical, short rods, threads, and spirals)
coccus
single round
cocci
multiple round
bacillus
single rod
bacilli
multiple rods
Give examples of why bacteria is important
produce oxygen, decomposition, nitrogen fixation, food and medicine, produce greenhouse gases
What is cell theory?
The idea that all living things are comprised of at least 1 cell and that all cells must rise from existing cells
Who first introduced aseptic technique?
Louis Pasteur
What is "pasteurization"
Brief heating of foods to kill most bacteria that cause it to spoil
Who first introduced antiseptic techniques
Joseph Lister, introduced sterilization with carbolic acid or phenol
What did Edward Jenner discover/invent
vaccines to rid of smallpox's
What did Alexander Fleming discover
identified penicillium and isolated penicillin which was effective against Gram + bacteria
Who proposed the current 3-domain system we currently utilize
Carl Woese
Give reasons why Microorganisms are difficult to study
most are invisible to naked eye, mixed in nature, need special tools and techniques
Prokaryotes (bacteria & archaea) have no _____________.
nucleus, PRO=NO
What are the functions of the glycocalyx
protect cells from dehydration and nutrient loss
inhibit killing by white blood cells
attachment to form biofilms
Who came up with the technique of Gram staining?
Sir Hans Gram
What dye acts the primary in Gram staining
Crystal Violet
What dye acts as the mordant in Gram staining
Iodine
What acts as the decolorizer in Gram staining
alcohol (ethanol)
What dye acts as the counterstain in Gram staining
Safranin
What are plasmids?
extrachromosomal, circular, double stranded DNA molecules found in bacteria
Which domain is considered extremophiles
Archaea
Eukaryotes include:
human, animal, fungi, algae, protozoans, helminths/worm cells
Eukaryotes have a ______ ribosome
80s
Prokaryotes have a _______ ribosome
70s
List some positive impacts that fungi can have
certain foods, decomposition, medicine, research (model organisms)
List some adverse impacts that fungi can have
disease causing, crop destruction, allergy
What is the dormant resting stage of a protozoa called
cyst